Many medical devices have visual screens for providing real-time data. While some have simple backlit 80×25 text screens, others require television screens or video monitors for displaying video images. The space in hospital operating room environments is very tight and cannot accommodate much equipment, especially bulky video monitors. The space close to a patient, where one or more physicians might operate, is more or less constrained by the geometry of the patient and the need or desire to have certain medical instruments in fixed locations, e.g., anesthesia devices near the patient's head region. Usable space near a patient, especially that which is directly accessible by the operating physician, is at a premium. When multiple medical devices each require a video monitor, the situation presents both space and ergonomic challenges to the physician and support staff as they attempt to coordinate the use of multiple video monitors. In some cases, it might be impracticable to accommodate more than one monitor near the patient. There is therefore a need for a system and method to allow physicians and support staff to use, and coordinate the use of, multiple imaging devices on a common monitor and storage system.
Imaging devices can have different native resolutions and frame rates. Focal Plane Array (FPA) devices typically use Charge Coupled Device (CCD) technology to capture an entire image, or frame, all at once. Typically, these CCD-type imagers capture 30 frames per second (fps). As the frame is rendered to a suitable video format for display on a monitor, the frame may be split into two interlaced (every other line) 60 fps frames that combined make up one full frame on the monitor. This interlacing tends to result in image degradation, but does have the advantage that common inexpensive equipment that supports interlaced video is ubiquitously available and interconnections between various pieces of equipment are relatively simple and straightforward. Alternatively, the FPA may present a progressive scan video signal, whereby each frame is imaged line by line in its entirety resulting in better clarity video. Progressive scan FPA devices and monitors tend to be somewhat more expensive than interlaced devices.
Scanned Beam Imaging (SBI) devices, on the other hand, use a different, higher resolution technology. Instead of acquiring the entire frame at once, the area to be imaged is rapidly scanned point-by-point by an incident beam of light, the reflected light being picked up by sensors and translated into a native data stream representing a series of points and values. SBI technology is especially applicable to endoscopes because SBI devices have better image resolution and present higher quality images of small internal structures, use reduced power light sources, and can be put in very small package diameters for insertion into a human body.
Scanning beam imaging endoscopes using bi-sinusoidal and other scanning patterns are known in the art; see, for example U.S. Patent Application US 2005/0020926 A1 to Wikloffet al. An exemplary color SBI endoscope has a scanning element that uses dichroic mirrors to combine red, green, and blue laser light into a single beam of white light that is then deflected off a small mirror mounted on a scanning bi-axial MEMS (Micro Electro Mechanical System) device. The MEMS device scans a given area with the beam of white light in a pre-determined bi-sinusoidal or other comparable pattern and the reflected light is sampled for a large number of points by red, green, and blue sensors. Each sampled data point is then put in a native SBI data format and transmitted to an image processing device.
While reading data out from FPA/CCD devices is normally performed in an orderly line-by-line manner that makes conversion to a standard video signal relatively straightforward, MEMS-based scanners using bi-sinusoidal or other non-standard scanning patterns result in an ordering of the SBI data that would be incompatible for direct use with ordinary monitors. Also, the image may be scanned at frame rates that ordinary monitors are not capable of refreshing on their screens. To display on an ordinary monitor, the scanned image is therefore first reassembled from the SBI digital pixel image data into a full frame image. This reassembling process is sometimes referred to as rasterization, because a raster or frame is created from the raw data. The image processing device then uses the full frame image to render an appropriate video signal to be displayed on a video monitor at a suitable frame rate.
A native SBI image has potentially superior digital pixel density and dynamic range than an FPA image. Preferentially, the SBI image should be displayed on a monitor suitable for directly displaying the SBI image from the SBI image data. Alternatively, the SBI image data should be converted to a format suitable for display on a high resolution video monitor. There is therefore a need for a system and method to allow physicians and support staff to use, and coordinate the use of, both FPA and SBI imaging devices on a common high resolution monitor and storage system.